Pros

Cons

Slow maximum aperture

Tripod mount could be included

Unsophisticated tripod mount design

Slightly “busy” bokeh

Lenses for full frame cameras in the range of around 100-400mm hit an extremely useful point in the focal length range. Birding, general wildlife, sports and portraiture all cry out for these lenses so an alternative to the generally expensive marque optics is always welcome. The Tamron 100-400mm f/4.5-6.3 Di VC USD lens is reviewed here using the Canon 5D SR body. Alongside this, we have the optional Tamron Tripod Mount M that is specifically designed for the lens and is included in the review.

Handling and Features

The lens is relatively compact for its specification, helped by the modest maximum aperture, appears well made and operates very smoothly. It weighs in at 1115g without caps or hood, 1180g with hood and 1320g with hood and tripod mount. Now although it is quite possible that higher end, solid DSLR mounts will happily carry the weight of the lens, it is arguable that it is much better to use the ARCA-SWISS compatible tripod mount. Doing so, especially using a camera carrying sling, means the lens and camera can be carried for hours without the weight being a problem. Inevitably, we pay for the tripod mount one way or another, but including it as standard might be a better route to take. Providing it as an optional extra cost, a further £109.99 on top of the lens price. The design of the tripod mount is pretty basic, requiring it to be loosened as a whole to rotate the lens for landscape or portrait orientation. It does an adequate job without finesse.

Taking our tour of the lens from the front, there is a large bayonet fit round lens hood provided, which locks securely into place. The filter thread is 67mm.

Behind this, the wide zoom ring is smooth and clearly marked with accurate focal lengths. There is a lock switch that enables the zoom to be fixed at 100mm, thus preventing the lens extending when being carried.

Moving closer to the camera body, the manual focusing ring can be used when the lens is set to AF, to switch instantly to manual focus. AF under these circumstances is resumed by taking the finger off the shutter release button and then resuming with a half press. A useful feature where a final tweak to the focus position is needed. Focusing does not alter the length of the lens, although zooming does.

Finally, forward of the tripod mount collar, there is a distance scale showing a guide in both feet and metres. There is no depth of field scale, and as it would probably be too cramped to be of use that is not really an issue. At this point on the lens barrel, there are two side switches. One is to switch the VC (Vibration Compensation) between Mode 1 (general use), Mode 2 (panning) and off. The other is to switch from AF, AF range limiter and MF. The limiter is set as standard to 7m to infinity or 1.5m to 7m. This is one of the parameters that can be adjusted using the optional Tamron TAP-In console. Closest focus is 1.5m or 59.1 inches, representing a maximum magnification of 1:3.6, usefully close.

The optical formula comprises 17 elements in 11 groups, including two LD (Low Dispersion). The coating is Tamron’s eBAND, extended bandwidth, version of multi-coating, with a fluorine coating on the front element to repel water and grease. The lens is moisture resistant. It is also compatible with Tamron’s 1.4x teleconverter, which extends the range significantly.

There is no doubt that 100-400mm is a very useful focal length range, bringing in all sorts of medium and long-range subject matter. It makes for a slightly unwieldy but manageable 100mm lens but a very easy to use 400mm, albeit with a fairly restricted maximum aperture. The VC system stabilises very quickly and the AF is fast and reliable. It makes an excellent match for the Canon 5D SR and would also for other full frame bodies. It can, of course, also be used on APS-C format bodies, where it would have an equivalent range of 150-600mm (Nikon) or 160-640mm (Canon).

Performance

Starting at 100mm, sharpness centrally is excellent from f/4.5 to f/11, very good at f/16 and then diffraction starts to really bite. Results are still good at f/22, but f/32 is really quite soft. At the edges, f/4.5 is good, f/5.6 to f/16 very good, but thereafter f/22 and f/32 are soft.

200mm sees excellent central sharpness from f/5.6 to f/11 which remains very good at f/16. It is still good at f/22 but thereafter falls to softness progressively from f/32 to f/40. At the edges, f/5.6 is very good, f/8 and f/11 excellent, f/16 very good. From f/22 to f/40 sees soft results.

300mm shows a very similar pattern. The centre is excellent from f/6.3 to f/11, very good at f/16 and only surrenders to diffraction from f/22 to f/45, which are progressively softer as we go. The edges start off at a very good level at f/6.3, are excellent at f/8, very good at f/11 and f/16 and then follow the central pattern of increasing softness from f/22 through to f/45.

400mm is where it can so easily fall apart, and yet the longest focal length is critical to the usefulness of the lens. Pleasingly, the central sharpness is very good from f/6.3 to f/16 and only falls into softness from f/22 to f/45. The edges are soft at f/6.3, good at f/8 and f/11 and then soften from f/16 through to f/45.

In practice, this is all very usable and the edge softness at 400mm and f/45 is not a likely combination to be often sought. To enable an adequate shutter speed to stop subject motion, for example in bird photography, open aperture or f/8 is much more likely to be selected and here the lens is largely excellent throughout its focal length range.

Tamron 100-400mm f/4.5-6.3 Di VC USD MTF Charts

MTF50 Graph At 100mm

MTF50 Graph At 200mm

MTF50 Graph At 300mm

MTF50 Graph At 400mm

How to read our MTF charts

The blue column represents readings from the centre of the picture frame at the various apertures and the green is from the edges.

The scale on the left side is an indication of actual image resolution as LW/PH and is described in detail above. The taller the column, the better the lens performance.

For this review, the lens was tested on a Canon 5DS R body here using Imatest.

CA (Chromatic Aberration) at the centre is extremely low at 100mm, steadily increasing as the focal length increases, but still delivering impressive figures. The edges are less well controlled, but again return impressive figures for a long zoom lens. As always, if fringing should be a problem on demanding subjects then software solutions are available.

Tamron 100-400mm f/4.5-6.3 Di VC USD Chromatic Aberration Charts

CA Graph At 100mm

CA Graph At 200mm

CA Graph At 300mm

CA Graph At 400mm

How to read our CA charts

Chromatic aberration (CA) is the lens’ inability to focus on the sensor or film all colours of visible light at the same point. Severe chromatic aberration gives a noticeable fringing or a halo effect around sharp edges within the picture. It can be cured in software.

Apochromatic lenses have special lens elements (aspheric, extra-low dispersion etc) to minimize the problem, hence they usually cost more.

For this review, the lens was tested on a Canon 5DS R body here using Imatest.

Pincushion distortion is found throughout, returning figures of +0.66% at 100mm, +1.51% at 200mm, +1.55% at 300mm and +1.61% at 400mm. This is actually considerably better than many zoom lenses, even those with less demanding specifications. Although it is unlikely that further correction will be needed for most subjects, if necessary we can turn to readily available software.

Excellent coating and internal construction plus a generously sized lens hood mean that flare is not a problem. It is not easy to induce and even contrast is maintained well against the light.

Bokeh is the quality, or smoothness of gradation, of the out of focus areas in an image. Large areas tend to blend well, but fine detail, for example, foliage behind a small bird, can look a little fussy, even slightly ragged. Fortunately, a long lens by its nature tends to throw backgrounds well out of focus, so it is acceptable.

Finally, the VC system does its job efficiently. Looking at it closely, it does depend to a slight degree of how sharp we want sharp to be, and the demands of an online image will be somewhat different to the demands of an A3+ print. This reviewer managed a good 2 stops advantage with critical sharpness maintained, and a 4 stop advantage with smaller prints and web in mind. In any event, a useful addition to the features of the lens.

Sample Photos

Tamron 100-400mm f/4.5-6.3 Di VC USD Zoom range

100mm

400mm

Verdict

The lens is very easy and satisfying to use and the price is certainly attractive. The optical performance is actually excellent overall, the sharpness only falling off at very small apertures. Of course, one of the unavoidable facts of optics is that at longer focal lengths those small apertures soon becomes very small indeed and very susceptible to diffraction effects. Bearing in mind though that high shutter speeds will likely be needed for wildlife and sports it is hardly a major issue.

Processed through Photoshop, with a bit of judicious sharpening where needed, the end results are crisp and very impressive.